Fluid Dynamics¶
Omniverse™ Flow is an Eulerian fluid simulation for smoke and fire, leveraging a sparse voxel grid for unbounded simulation domain.
Using Omniverse™ Flow¶
Getting Started¶
To start using Omniverse™ Flow, the omni.flowusd extension must be enabled. Make sure omni.flowusd is enabled in the Window->Extensions window.
Omniverse™ Flow must also be enabled in the RTX renderer. Enable Flow in Common Render Settings

Presets¶
Presets are the fastest way to get a working Flow effect. They can be created through Flow->Preset.

Press Play to begin simulation.

Flow->Preset->Set Postprocessing is also useful to quickly enable bloom to make fire appear bright.
Render Settings¶
For more light interaction, the following render settings can be enabled. Can also enable bloom and indirect diffuse GI.

Manual Setup¶
A working simulation can also be achieved by adding the necessary Flow prims to a stage. Simulate/Offscreen/Render Settings are required for any simulation. Be sure to enable Flow in the Common Render Settings. (Presets do this automatically.)

Press Play to begin simulation.

Layers¶
Flow layers provide a mechanism to allow multiple effects at the same time, sharing the same memory pool. UI is currently low level, with layers being specified by a simple integer. For a simulation to behave properly, an emitter and simulate/offscreen/render settings must all share a common layer. Flow presets automatically assign a unique layer, to prevent collisions with other presets. The UI for layers will be improved with future releases.
As an example, create a fire preset as specified above. Now Flow->Add Box Emitter. Delete the flowEmitterSphere in the stage.

At this point, no simulation will occur. Select flowSimulate in the stage to inspect its layer assignment.

Select flowEmitterBox and set its layer attribute to the same value. Visual simulation should now occur.

Colormap¶
The omni.flowusd also includes a simple colormap editor to change the mapping of temperature to color. Flow->Open Colormap Editor will open the colormap editor window. For the fire preset above, selecting flowOffscreen/colormap in the stage will populate the colormap editor.

Note for fire, colormap values can far exceed 1.0. This is needed for properly interaction with bloom. Once values are adjusted, hit Apply Flow Color to see changes applied.

Understanding Omniverse™ Flow¶
Cell Size¶
Cell Size has one of the most significant impacts on both appearance and performance. Keep in mind cutting cell size in half is an 8x increase in cells and as a result simulation time.
Channels¶
Flow currently has standard channels. The four density channels are temperature, fuel, burn, smoke, packed in that order. The four velocity channels are velocity_x, velocity_y, velocity_z, divergence, packed in that order. Advection and emitters expose independent parameters for each of those channels.
Couple Rate¶
Couple rate is used on Flow emitters. It specifices a rate of correction between an existing grid value and a target emitter value. Higher values like 120 can take the grid instantly to the emitter target values. High couple rates can be useful with fast moving emitters. Lower couple rates are very useful for slow moving emitters. By making the move towards the target value lazy, simulation can actively occur inside the emitter. This typically results in less artifacts and a more natural transition from inside to outside the emitter.
Effect Lifetime¶
The damping/fade on advection largely controls effect lifetime. Damping is proportional to the current grid value. Fade is a fixed units / second rate.
Effect Scale¶
Vorticity forceScale has a significant impact on perceived scale. Higher forceScale tends to make effects appear larger.
Combustion Modeling¶
Default today includes a simple combustion model. Settings like buoyancyPerBurn help create mushroom cloud motion expected from explosions. Parameters like burnPerTemp and fuelPerBurn can also affect how fast combustion occurs. divergencePerBurn also controls expansion due to combustion. Higher values are useful for explosions.
Velocity¶
With velocity, more is not always more. This simulation is based on stable fluids, where high velocities don’t necessarily behave as expected, but the simulation does not explode. Coarser cell size will effectively behave better will higher world scale velocities. Support for velocity substepping and overall shorter simulation steps are exposed, that improve high velocity behavior with a performance cost.
Rendering¶
Rendering today uses the Omniverse™ Flow reference implementation. Future versions will likely lean on native volume support in the RTX renderer. Basic Omniverse™ Flow rendering provides a colormap to map temperature to color/alpha for fire/smoke. Also included is self shadowing.
Collision¶
Collision support today is very limited. However emitters can be adapted for this purpose. Set allocationScale to 0.0, since collision only needs to be active when the simulation is visibly active. Set temperature/fuel/burn/smoke/divergence couple rates to zero, as we only need to control velocity. Set target velocity to (0, 0, 0). Set physicsVelocityScale to 1.0 for moving objects, to include body velocity. Set coupleRateVelocity to 120 or higher, to drive velocity to body velocity within a single frame. Set applyPostPressure to true, as this guarantees velocity at the end of the frame will match body velocity.
Settings¶
Simulate Settings¶
Property |
Result |
---|---|
blockMinLifetime |
Minimum lifetime of any allocate block. Avoids premature deactivation caused by GPU readback delay.
|
densityCellSize |
Size of density cells in world units. By default velocity cell size is twice density cell size.
|
enableSmallBlocks |
Use 16x8x8 density cell blocks instead of the default 32x16x16
|
enableVariableTimeStep |
Take step every frame. Can cause inconsistent simulation behavior for highly variable time step values, but useful when frame time is fixed already.
|
forceClear |
Kills all active block allocations in this layer
|
forceDisableCoreSimulation |
Disable most simulation components. Emitters still function.
|
forceDisableEmitters |
Disable all emitters in this layer
|
forceSimulate |
Force simulate, even if timeline is paused.
|
interpolateTimeSteps |
Useful for motion blur in movie capture. Produces sub-frames between full simulation steps.
|
layer |
See Layer section above.
|
maxStepsPerSimulate |
Limit on steps per frame to avoid excessive steps when application is running slow.
|
simulateWhenPaused |
Run simulation even if deltaTime is 0.0.
|
stepsPerSecond |
Simulation update rate
|
timeScale |
Scales input time. Useful for slomo.
|
velocitySubSteps |
Higher values improve behavior with high speed effects, at the cost of performance.
|
advection |
See Advection section.
|
vorticity |
See Vorticity section.
|
pressure |
See Pressure section.
|
summaryAllocate |
See SummaryAllocate section.
|
Advection¶
Property |
Result |
---|---|
buoyancyMaxSmoke |
Smoke clamp value applied before computing smoke buoyancy, default 1.0
|
buoyancyPerSmoke |
Buoyant force per unit smoke, default 0.0
|
buoyancyPerTemp |
Upward force relative to temperature. Higher values help produce mushroom effects.
|
burnPerTemp |
Rate of burn relative to temperature. Higher burn values affect fuel consumption and
divergence (expansion) terms.
|
coolingRate |
Temperature fade, applied on a per cell level. (Not conduction/convection.)
|
divergencePerBurn |
Expansion relative to burn amount. Units comparable to velocity in terms of scale.
Higher values produce visible expansion, but can remove detail.
|
downsampleEnabled |
Boolean to enable/disable downsample. Downsample needed for SummaryAllocate
|
enabled |
Boolean to enable/disable advection.
|
fuelPerBurn |
Fuel consumed relative to burn amount. Lower values will make a given amount of fuel
last longer.
|
globalFetch |
Improves advection quality for high velocities, with some increase in runtime cost.
(Can remove some banding artifacts)
|
gravity |
Used to determine the ‘up’ direction for buoyancy.
|
ignitionTemp |
Minimum temperature for combustion.
|
smokePerBurn |
Smoke increase relative to burn amount.
|
tempPerBurn |
Temperature increase relative to burn amount.
|
smoke |
See Advection Channel section.
|
velocity |
See Advection Channel section.
|
divergence |
See Advection Channel section.
|
temperature |
See Advection Channel section.
|
fuel |
See Advection Channel section.
|
burn |
See Advection Channel section.
|
Advection Channel¶
Property |
Result |
---|---|
damping |
Reduce channel proportional to current value. Valid range is 0 to 1, where 1
takes the value to 0 immediately.
|
fade |
Reduce channel at a constant rate per second. Valid range is 0 to infinity
effectively.
|
secondOrderBlendFactor |
Second order correction factor. Value range is 0.0 to 1.0. 0.5 is generally a
safe default. Higher values increase the sharpness, but comes with potentially
banding artifacts. Use extra caution with velocity, where effects are even
more pronounced.
|
secondOrderBlendThreshold |
Minimum value to apply second order correction. Reduces simulation cost for cells
near zero, with minimal/zero visual artifacts.
|
Vorticity¶
Property |
Result |
---|---|
burnMask |
Allows force to be applied relative to burn value in grid.
|
constantMask |
Allows force to be applied without respect to local velocity.
|
densityMask |
Allows force to be applied relative to divergence (Parameter name
should be fixed.)
|
enabled |
Boolean to enable/disable vorticity confinement.
|
forceScale |
Control intensity of effect
|
fuelMask |
Allows force to be applied relative to fuel value in grid.
|
smokeMask |
Allows force to be applied relative to smoke value in grid.
|
temperatureMask |
Allows force to be applied relative to temperature value in grid.
|
velocityLinearMask |
Makes force directly proportional to local velocity
Math: velocityLinearMask * speed
|
velocityLogScale |
This primarily exists to allow rescaling of Omniverse™ Flow effects to different
coordinate systems.
|
velocityMask |
Velocity log mask, works together with velocityLogScale. Makes local linear
velocity a requirement for forces to be applied. The log part makes the force
applied with respect to velocity a diminishing return to avoid instability.
|
Pressure¶
Property |
Result |
---|---|
enabled |
Boolean to enable/disable the pressure solver.
|
SummaryAllocate¶
Property |
Result |
---|---|
smokeThreshold |
Minimum smoke to keep a block active.
|
speedThreshold |
Minimum speed to keep a block active, given
speedThresholdMinSmoke is satisfied.
|
speedThresholdMinSmoke |
Minimum smoke value for speedThreshold to apply.
|
Offscreen Settings¶
Property |
Result |
---|---|
layer |
Layer ID to apply these settings to
|
colormap |
See Colormap section.
|
shadow |
See Shadow section.
|
debugVolume |
See DebugVolume section.
|
Colormap¶
Property |
Result |
---|---|
resolution |
Number of texels in colormap
|
rgabPoints |
RGBA values of control points, RGB can be over 1.0 for HDR effects.
|
xPoints |
X coordinates of control points, maps to temperature. Valid over 0 to 1
|
Shadow¶
Property |
Result |
---|---|
attenuation |
Rate of light blockage. Higher values increase self shadow effect.
|
coarsePropagate |
Compute shadows at 2x2x2 coarser grid. Provides good
quality at a much lower runtime cost.
|
enabled |
Boolean to enable/disable self shadowing.
|
isPointLight |
If true, point light, else directional light.
|
lightDirection |
Directional light. Points to light.
|
lightPosition |
Point light position.
|
minIntensity |
Provide ambient level
|
numSteps |
Number of steps per self shadow ray, divide by 2 when
coarsePropagate is enabled.
|
stepOffsetScale |
Ray march offset to avoid a cell shadowing itself.
|
stepSizeScale |
Ray march step size relative to cell size. Higher values increase
quality and performance cost.
|
DebugVolume¶
Property |
Result |
---|---|
enableSpeedAsTemperature |
Write speed value to temperature channel, to visualize in ray march.
|
enableVelocityAsDensity |
Write abs() of velocity channels to density xyz to visualize in ray march.
|
velocityScale |
Scale applied to velocity to control brightness for ray march result.
|
Render Settings¶
Property |
Result |
---|---|
layer |
Layer ID to apply these settings to
|
rayMarch |
See RayMarch section
|
RayMarch¶
Property |
Result |
---|---|
attenuation |
Rate of light blockage. Higher values make the volume look more opaque
|
enableBlockWireframe |
Visualizes active blocks for debug purposes
|
enableRawMode |
If true, do not apply colormap, pass raw density xyzw as color
|
shadowFactor |
The degree to which the z shadow channel scales the RGB channels from
the colormap. 1.0 is default. 0.0 disables self shadowing effectively.
|
stepSizeScale |
Ray march step size relative to cell size. Higher values increase
quality and performance cost.
|
cloud |
See RayMarchCloud section.
|
RayMarchCloud¶
Property |
Result |
---|---|
ambientColor |
Color in shadowed regions.
|
ambientMultiplier |
Scale to adjust brightness of ambient color.
|
attenuationMultiplier |
Controls how fast cloud shadows go dark.
|
densityMultiplier |
Scales input density.
|
enableCloudMode |
If true, default ray march is disabled, these settings are used instead.
|
numShadowSteps |
More steps can improve quality, but add performance cost.
|
shadowStepMultiplier |
Larger steps cover more of world space, at risk of artifacts.
|
sunDirection |
Direction to sun.
|
volumeBaseColor |
Base color for scattering.
|
volumeColorMultiplier |
Scale to adjust brightness of volume base color.
|
Emitter Sphere¶
Sphere emitters are the simplest emitter type. Defined by a position and radius.
Property |
Result |
---|---|
allocationScale |
1.0 allocates blocks needed to contain sphere. 0.0 disables allocation.
Values higher than 1.0 can be used to add additional padding.
|
applyPostPressure |
If true, apply velocity after pressure solve. This is useful
for collision, as it allows hard enforcement of velocity inside
moving bodies.
|
burn |
Target burn value.
|
coupleRateBurn |
Couple rate for burn channel.
|
coupleRateDivergence |
Couple rate for divergence channel.
|
coupleRateFuel |
Couple rate for the fuel channel.
|
coupleRateSmoke |
Couple rate for the smoke channel.
|
coupleRateTemperature |
Couple rate for the temperature channel.
|
coupleRateVelocity |
Couple rate for the velocity channel.
|
divergence |
Target divergence value.
|
enabled |
Boolean to enable/disable emitter
|
fuel |
Target fuel value.
|
layer |
Layer ID of simulation this emitter effects
|
multisample |
Test sphere overlap at 8 locations instead of 1
|
numSubSteps |
Substeps per simulation update. More steps produce a smoother result with moving emitters.
|
physicsVelocityScale |
If set to 1.0, the body velocity will be added to the target velocity.
This is useful for collision effects, where the body velocity
and grid cell velocity should align.
|
position |
Position of sphere
|
radius |
World space radius of sphere
|
smoke |
Target smoke value.
|
temperature |
Target temperature value.
|
velocity |
Target velocity value.
|
Emitter Box¶
Box emitters support emission from an oriented box. Clipping planes can also be added to support convex hulls.
Property |
Result |
---|---|
allocationScale |
1.0 allocates blocks needed to contain box. 0.0 disables allocation.
Values higher than 1.0 can be used to add additional padding.
|
applyPostPressure |
If true, apply velocity after pressure solve. This is useful for
collision, as it allows hard enforcement of velocity inside moving bodies.
|
burn |
Target burn value.
|
clippingPlanes |
List of clipping planes in local space.
|
coupleRateBurn |
Couple rate for burn channel.
|
coupleRateDivergence |
Couple rate for divergence channel.
|
coupleRateFuel |
Couple rate for the fuel channel.
|
coupleRateSmoke |
Couple rate for the smoke channel.
|
coupleRateTemperature |
Couple rate for the temperature channel.
|
coupleRateVelocity |
Couple rate for the velocity channel.
|
divergence |
Target divergence value.
|
enabled |
Boolean to enable/disable emitter
|
fuel |
Target fuel value.
|
halfSize |
Half of box width/height/depth in local units
|
layer |
Layer integer. See Layer section.
|
multisample |
Test sphere overlap at 8 locations instead of 1
|
physicsVelocityScale |
If set to 1.0, the body velocity will be added to the target velocity.
This is useful for collision effects, where
the body velocity and grid cell velocity should align.
|
smoke |
Target smoke value.
|
temperature |
Target temperature value.
|
velocity |
Target velocity value.
|
Emitter Point¶
Point emitters allow simple arrays to define points that are splatted to the simulation.
Property |
Result |
---|---|
allocateMask |
Default allocation behavior. If true and allocateMasks is empty, all points will trigger allocation.
|
applyPostPressure |
If true, apply velocity after pressure solve.
This is useful for collision, as it allows hard enforcement of velocity inside moving bodies.
|
burn |
Default target burn value.
|
coupleRateBurn |
Default couple rate for burn channel.
|
coupleRateDivergence |
Default couple rate for divergence channel.
|
coupleRateFuel |
Default couple rate for fuel channel.
|
coupleRateSmoke |
Default couple rate for smoke channel.
|
coupleRateTemperature |
Default couple rate for temperature channel.
|
coupleRateVelocity |
Default couple rate for velocity channel.
|
divergence |
Default target divergence value.
|
enabled |
Boolean to enable/disable emitter
|
fuel |
Default target fuel value.
|
layer |
Layer integer. See Layer section.
|
pointAllocateMasks |
Optional array of allocate settings per point.
|
pointBurns |
Array of target burn values for each position.
|
pointCoupleRateBurns |
Array of burn couple rates for each position.
|
pointCoupleRateDivergences |
Array of divergence couple rates for each position.
|
pointCoupleRateFuels |
Array of fuel couple rate for each position.
|
pointCoupleRateSmokes |
Array of smoke couple rates for each position.
|
pointCoupleRateTemperatures |
Array of temperature couple rates for each position.
|
pointCoupleRateVelocities |
Array of velocity couple rates for each position.
|
pointDivergences |
Array of target divergence values for each position.
|
pointFuels |
Array of target fuel values for each position
|
pointPositions |
Array of local space positions. Determines total point count.
|
pointSmokes |
Array of target smoke values for each position
|
pointTemperatures |
Array of target temperature values for each position.
|
pointVelocities |
Array of target velocity values for each position.
|
smoke |
Default target smoke value.
|
temperature |
Default target temperature value.
|
velocity |
Default target velocity value.
|
Emitter Texture¶
Texture emitters allow simple arrays to define dense 3D grids of values.
Note
Mapping of Array Index to Texel: arrayIndex = (texelIndex.z * textureHeight + texelIndex.y) * textureWidth + texelIndex.x
Property |
Result |
---|---|
allocationScale |
1.0 allocates blocks needed to contain box defined by halfSize/position. 0.0 disables allocation. Values higher than 1.0 can be used to add
additional padding.
|
applyPostPressure |
If true, apply velocity after pressure solve.
This is useful for collision, as it allows hard enforcement of velocity inside moving bodies.
|
burn |
Default target burn value.
|
coupleRateBurn |
Default couple rate for burn channel.
|
coupleRateDivergence |
Default couple rate for divergence channel.
|
coupleRateFuel |
Default couple rate for fuel channel.
|
coupleRateSmoke |
Default couple rate for smoke channel.
|
coupleRateRateTemperature |
Default couple rate for temperature channel.
|
coupleRateVelocity |
Default couple rate for velocity channel.
|
divergence |
Default target divergence value.
|
enabled |
Boolean to enable/disable emitter.
|
fuel |
Default target fuel value.
|
halfSize |
Half of box width/height/depth in world units.
|
layer |
Layer integer. See Layer section.
|
position |
World space position.
|
smoke |
Default target smoke value.
|
temperature |
Default target temperature value.
|
textureBurns |
Array of target burn values for each texel.
|
textureCoupleRateBurns |
Array of burn couple rates for each texel.
|
textureCoupleRateDivergences |
Array of divergence couple rates for each texel.
|
textureCoupleRateFuels |
Array of fuel couple rate for each texel.
|
textureCoupleRateSmokes |
Array of smoke couple rates for each texel.
|
textureCoupleRateTemperatures |
Array of temperature couple rates for each texel.
|
textureCoupleRateVelocities |
Array of velocity couple rates for each texel.
|
textureDepth |
Depth in texels of texture data.
|
textureDivergences |
Array of target divergence values for each texel.
|
textureFirstElement |
Array index offset applied for all arrays. Useful for animation.
|
textureFuels |
Array of target fuel values for each texel.
|
textureHeight |
Height in texels of texture data.
|
textureSmokes |
Array of target smoke values for each texel.
|
textureTemperatures |
Array of target temperature values for each texel.
|
textureVelocities |
Array of target velocity values for each texel.
|
textureWidth |
Width in texels of texture data.
|
velocity |
Default target velocity value.
|
Emitter NanoVDB¶
NanoVDB emitters allow sparse voxel data structures to define emitter shapes/values.
Property |
Result |
---|---|
allocateActiveLeaves |
If true, finer allocation granularity is used. (Adds some CPU overhead.)
|
allocationScale |
1.0 allocates blocks needed to contain NanoVDB. 0.0 disables allocation. Values higher than 1.0 can be used to add
additional padding.
|
applyPostPressure |
If true, apply velocity after pressure solve.
This is useful for collision, as it allows hard enforcement of velocity inside moving bodies.
|
burn |
Default target burn value.
|
coupleRateBurn |
Default couple rate for burn channel.
|
coupleRateDivergence |
Default couple rate for divergence channel.
|
coupleRateFuel |
Default couple rate for fuel channel.
|
coupleRateSmoke |
Default couple rate for smoke channel.
|
coupleRateTemperature |
Default couple rate for temperature channel.
|
coupleRateVelocity |
Default couple rate for velocity channel.
|
divergence |
Default target divergence value.
|
enabled |
Boolean to enable/disable emitter
|
fuel |
Default target fuel value.
|
layer |
Layer integer. See Layer section.
|
maxDistance |
Maximum distance for emitter active region. Used with nanoVdbDistances.
|
minDistance |
Minimum distance for emitter active ergion. Used with nanoVdbDistances.
|
nanoVdbBurnFirstElement |
Burn channel. Word offset applied when reading nanoVdbBurns array.
|
nanoVdbBurns |
Burn channel. Word array containing NanoVDB data structure
|
nanoVdbBurns::assetPath |
Burn channel. Optional path to OpenVDB/NanoVDB asset to use. Overrides nanoVdbBurns.
|
nanoVdbBurns::gridName |
Burn channel. Grid name to search for in NanoVDB data structure.
|
nanoVdbCoupleRateBurnFirstElement |
Burn couple rate channel. Word offset applied when reading nanoVdbCoupleRateBurns array.
|
nanoVdbCoupleRateBurns |
Burn couple rate channel. Word array containing NanoVDB data structure
|
nanoVdbCoupleRateBurns::assetPath |
Burn couple rate channel. Optional path to OpenVDB/NanoVDB asset to use. Overrides nanoVdbCoupleRateBurns.
|
nanoVdbCoupleRateBurns::gridName |
Burn couple rate channel. Grid name to search for in NanoVDB data structure.
|
nanoVdbCoupleRateDivergenceFirstElement |
Divergence couple rate channel. Word offset applied when reading nanoVdbCoupleRateDivergences array.
|
nanoVdbCoupleRateDivergences |
Divergence couple rate channel. Word array containing NanoVDB data structure
|
nanoVdbCoupleRateDivergences::assetPath |
Divergence couple rate channel. Optional path to OpenVDB/NanoVDB asset to use. Overrides nanoVdbCoupleRateDivergences.
|
nanoVdbCoupleRateDivergences::gridName |
Divergence couple rate channel. Grid name to search for in NanoVDB data structure.
|
nanoVdbCoupleRateFuelFirstElement |
Fuel couple rate channel. Word offset applied when reading nanoVdbCoupleRateFuels array.
|
nanoVdbCoupleRateFuels |
Fuel couple rate channel. Word array containing NanoVDB data structure
|
nanoVdbCoupleRateFuels::assetPath |
Fuel couple rate channel. Optional path to OpenVDB/NanoVDB asset to use. Overrides nanoVdbCoupleRateFuels.
|
nanoVdbCoupleRateFuels::gridName |
Fuel couple rate channel. Grid name to search for in NanoVDB data structure.
|
nanoVdbCoupleRateSmokeFirstElement |
Smoke couple rate channel. Word offset applied when reading nanoVdbCoupleRateSmokes array.
|
nanoVdbCoupleRateSmokes |
Smoke couple rate channel. Word array containing NanoVDB data structure
|
nanoVdbCoupleRateSmokes::assetPath |
Smoke couple rate channel. Optional path to OpenVDB/NanoVDB asset to use. Overrides nanoVdbCoupleRateSmokes.
|
nanoVdbCoupleRateSmoke::gridName |
Smoke couple rate channel. Grid name to search for in NanoVDB data structure.
|
nanoVdbCoupleRateTemperatureFirstElement |
Temperature couple rate channel. Word offset applied when reading nanoVdbCoupleRateTemperatures array.
|
nanoVdbCoupleRateTemperatures |
Temperature couple rate channel. Word array containing NanoVDB data structure
|
nanoVdbCoupleRateTemperatures::assetPath |
Temperature couple rate channel. Optional path to OpenVDB/NanoVDB asset to use. Overrides nanoVdbCoupleRateTemperatures.
|
nanoVdbCoupleRateTemperature::gridName |
Temperature couple rate channel. Grid name to search for in NanoVDB data structure.
|
nanoVdbCoupleRateVelocities |
Velocity couple rate channel. Word array containing NanoVDB data structure
|
nanoVdbCoupleRateVelocities::assetPath |
Velocity couple rate channel. Optional path to OpenVDB/NanoVDB asset to use. Overrides nanoVdbCoupleRateVelocities.
|
nanoVdbCoupleRateVelocities::gridName |
Velocity couple rate channel. Grid name to search for in NanoVDB data structure.
|
nanoVdbCoupleRateVelocityFirstElement |
Velocity couple rate channel. Word offset applied when reading nanoVdbCoupleRateVelocities array.
|
nanoVdbDistanceFirstElement |
Distance channel. Word offset applied when reading nanoVdbDistances array.
|
nanoVdbDistances |
Distance channel. Word array containing NanoVDB data structure
|
nanoVdbDistances::assetPath |
Distance channel. Optional path to OpenVDB/NanoVDB asset to use. Overrides nanoVdbDistances.
|
nanoVdbDistances::gridName |
Distance channel. Grid name to search for in NanoVDB data structure.
|
nanoVdbDivergenceFirstElement |
Divergence channel. Word offset applied when reading nanoVdbDivergences array.
|
nanoVdbDivergences |
Divergence channel. Word array containing NanoVDB data structure
|
nanoVdbDivergences::assetPath |
Divergence channel. Optional path to OpenVDB/NanoVDB asset to use. Overrides nanoVdbDivergences.
|
nanoVdbDivergences::gridName |
Divergence channel. Grid name to search for in NanoVDB data structure.
|
nanoVdbFuelFirstElement |
Fuel channel. Word offset applied when reading nanoVdbFuels array.
|
nanoVdbFuels |
Fuel channel. Word array containing NanoVDB data structure
|
nanoVdbFuels::assetPath |
Fuel channel. Optional path to OpenVDB/NanoVDB asset to use. Overrides nanoVdbFuels.
|
nanoVdbFuels::gridName |
Fuel channel. Grid name to search for in NanoVDB data structure.
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nanoVdbSmokeFirstElement |
Smoke channel. Word offset applied when reading nanoVdbSmokes array.
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nanoVdbSmokes |
Smoke channel. Word array containing NanoVDB data structure
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nanoVdbSmokes::assetPath |
Smoke channel. Optional path to OpenVDB/NanoVDB asset to use. Overrides nanoVdbSmokes.
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nanoVdbSmokes::gridName |
Smoke channel. Grid name to search for in NanoVDB data structure.
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nanoVdbTemperatureFirstElement |
Temperature channel. Word offset applied when reading nanoVdbTemperatures array.
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nanoVdbTemperatures |
Temperature channel. Word array containing NanoVDB data structure
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nanoVdbTemperatures::assetPath |
Temperature channel. Optional path to OpenVDB/NanoVDB asset to use. Overrides nanoVdbTemperatures.
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nanoVdbTemperatures::gridName |
Temperature channel. Grid name to search for in NanoVDB data structure.
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nanoVdbVelocities |
Velocity channel. Word array containing NanoVDB data structure
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nanoVdbVelocities::assetPath |
Velocity channel. Optional path to OpenVDB/NanoVDB asset to use. Overrides nanoVdbVelocities.
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nanoVdbVelocities::gridName |
Velocity channel. Grid name to search for in NanoVDB data structure.
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nanoVdbVelocityFirstElement |
Velocity channel. Word offset applied when reading nanoVdbVelocities array.
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smoke |
Default target smoke value.
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temperature |
Default target temperature value.
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velocity |
Default target velocity value.
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